Pillow/src/PIL/ImageMode.py

65 lines
1.6 KiB
Python

#
# The Python Imaging Library.
# $Id$
#
# standard mode descriptors
#
# History:
# 2006-03-20 fl Added
#
# Copyright (c) 2006 by Secret Labs AB.
# Copyright (c) 2006 by Fredrik Lundh.
#
# See the README file for information on usage and redistribution.
#
# mode descriptor cache
_modes = None
class ModeDescriptor:
"""Wrapper for mode strings."""
def __init__(self, mode, bands, basemode, basetype):
self.mode = mode
self.bands = bands
self.basemode = basemode
self.basetype = basetype
def __str__(self):
return self.mode
def getmode(mode):
"""Gets a mode descriptor for the given mode."""
global _modes
if not _modes:
# initialize mode cache
from . import Image
modes = {}
# core modes
for m, (basemode, basetype, bands) in Image._MODEINFO.items():
modes[m] = ModeDescriptor(m, bands, basemode, basetype)
# extra experimental modes
modes["RGBa"] = ModeDescriptor("RGBa", ("R", "G", "B", "a"), "RGB", "L")
modes["LA"] = ModeDescriptor("LA", ("L", "A"), "L", "L")
modes["La"] = ModeDescriptor("La", ("L", "a"), "L", "L")
modes["PA"] = ModeDescriptor("PA", ("P", "A"), "RGB", "L")
# mapping modes
for i16mode in (
"I;16",
"I;16S",
"I;16L",
"I;16LS",
"I;16B",
"I;16BS",
"I;16N",
"I;16NS",
):
modes[i16mode] = ModeDescriptor(i16mode, ("I",), "L", "L")
# set global mode cache atomically
_modes = modes
return _modes[mode]